Bombardier registered a much-welcome letter of intent (LOI) for the C Series CS300 on Tuesday at the Dubai Air Show, when Turkish low-fare carrier Atlasjet signed for 15 of the new narrowbodies. The potential contract, worth as much as $1.18 billion if Atlasjet exercises a further five options covered by the LOI, could become firm by year-end, said Bombardier vice president of sales Chet Fuller.

Schedules still call for the 125- to 145-seat CS300–the larger of the two C Series variants–to gain certification at the end of 2014. Atlasjet plans to take deliveries from the first quarter of 2016 through mid-2017. Although Bombardier hasn’t released information on seat capacity, Fuller did confirm that Atlasjet plans to take the airplanes with a high-density, single-class configuration. Bombardier expects authorities to certify the 110- to 125-seat CS100 in late 2013.

Now holding firm orders for 133 C Series airliners, Bombardier continues to talk with Qatar Airways about a prospective order, said Bombardier Aerospace president and COO Guy Hachey. In charge of the C Series program since the retirement of Gary Scott in October, Hachey said he expects to name a successor for Scott some time around the end of this year.

Fuller said Bombardier has sold out all its slots for the C Series through 2014 and that it holds “a couple” for prospective customers in 2015.